What is a roof that has a slope of less than or equal to 4 in 12 referred to as?

A roof that has a slope of less than or equal to 4 in 12 is classified as a low-slope roof. This designation is based on the measurement of the roof's slope, which is expressed as the ratio of vertical rise to horizontal run. In this case, a slope of 4 in 12 means that for every 12 horizontal inches, the roof rises 4 inches.

Low-slope roofs are typically less than 3:12 in steepness, but they can go up to 4:12 and still be considered low-slope. This category is vital in roofing because it influences how water drains off the roof and dictates the types of roofing materials and systems that can be safely and effectively used. Understanding this classification is essential for assessing proper roofing installation and maintenance, especially regarding drainage and waterproofing solutions.